This invention concerns a decoration method and particularly but not exclusively a decoration method usable on products such as items of tableware.
Presently a wide range of decoration methods and techniques are applied to items such as tableware, e.g. cups, plates, teapots etc. It is desirable to produce new affects in such decoration. It is also generally a requirement that such decorations should be durable and also dishwasher proof.
Thermochromic inks are materials which at a specified temperature change colour, or become transparent or at least translucent.
According to the present invention there is provided a method of decorating an article, the method comprising mixing a thermochromic ink with a first coating material, applying the mixture onto part or all of a surface of the article, once the mixture is set applying a second coating material onto said surface of the article.
The second coating material is preferably transparent. The second coating material is desirably substantially dishwasher proof.
The first coating material is preferably transparent.
The first and/or second coating materials preferably comprise lacquers. The first coating material preferably comprises an organic water based lacquer, though the lacquer could be acrylic based. The second coating material preferably comprises a two-part epoxy fortified acrylic resin, including an activator and a thinner.
The proportion of ink in the mixture is preferably within the range 5-25%.
The mixture and/or second coating material are preferably cured following application onto the article. The curing preferably commences with a period in an infra red shortwave drier followed by a heat cure. The heat cure preferably comprises a lower temperature first period, followed by a higher temperature second period. For the mixture, the first period preferably lasts between one and two minutes at 35xc2x0 C. to 65xc2x0 C., with the second period lasting eight to twelve minutes at 140 to 220xc2x0 C. For the second coating the first period preferably lasts between eight and twelve minutes at 35 to 65xc2x0 C., with the second period lasting twenty five to thirty minutes at 110 to 165xc2x0 C.
A decoration may be provided on the article beneath the mixture such that when the thermochromic ink is at least translucent, said decoration is visible.
The mixture may comprise a plurality of thermochromic inks with different colour change temperatures, and the inks may be of different colours.
The mixture and/or second coating material may be applied to the article by spraying, and desirable electrostatic spraying. In the latter case, an electrostatic thinner may be added to the mixture and/or second coating prior to spraying.
The mixture and/or the second coating material are preferably sprayed to a thickness of between 12 and 24 microns.